http://hdl.handle.net/10453/215 2013-05-23T16:54:54Z 2013-05-23T16:54:54Z Walker Jill Dorrell David Cossar Calum http://hdl.handle.net/10453/12819 2013-04-19T00:42:20Z 2005-01-01T00:00:00Z

Flux-linkage calculation in permanent-magnet motors using the frozen permeabilities method Walker Jill; Dorrell David; Cossar Calum Finite-element analysis can be used to determine the magnetization characteristics in terms of curves of flux-linkage against current or rotor position. The "frozen permeabilities" technique is presented as a method of apportioning flux-linkage contributions to the phase currents and permanent magnets, and for inductance calculations. Results from a split-phase interior permanent magnet motor are presented and compared with experimental data. Drawbacks to the method are discussed.

2005-01-01T00:00:00Z Kandasamy Jaya Beecham Simon Dunphy Alison http://hdl.handle.net/10453/12817 2013-01-22T22:15:11Z 2008-01-01T00:00:00Z

Stormwater sand filters in water sensitive urban design Kandasamy Jaya; Beecham Simon; Dunphy Alison This paper investigates the suitability of sand filters for harvesting and treating stormwater for non-potable reuse purposes. A stormwater sand filtration device was constructed in a small urban catchment in Sydney, Australia. A sand filter is typically used in water-sensitive urban design (WSUD) as a component of a treatment train to remove pollution from stormwater before discharge to receiving waters, to groundwater or for collection and reuse. This paper describes an 18 month field study undertaken to determine the effectiveness and pollutant removal efficiency of a sand filter, and the differences in the pollutant removal efficiency of two grades of sand. A comparison of pollutant removal with previous literature on sand filters showed similar efficiencies but nutrient removal was higher than expected. A further unexpected result was that the coarse filter media performed as well as the fine media for most pollutant types and was superior in suspended solids removal. Improved modelling equations for predicting suspended solids and total phosphorus removal in sand filters are also presented in this paper.

2008-01-01T00:00:00Z Fam Dena Mellick-Lopes Abby Willetts Juliet Mitchell Cynthia http://hdl.handle.net/10453/12814 2011-10-05T03:55:16Z 2009-01-01T00:00:00Z

The challenge of system change: an historical analysis of Sydney's sewer systems Fam Dena; Mellick-Lopes Abby; Willetts Juliet; Mitchell Cynthia Despite the obvious health benefits of the sanitary revolution and construction of sewered systems, there are increasing doubts about the long term sustainability of centralised, water-based sanitation. Growing uncertainties such as rapid population growth, emergence of new pollutants, changing hydrological conditions in relation to climate change and global economic instability will require systems to be more open to `flexible and reflexive approaches1 in meeting future sanitation needs. The highly inflexible nature of existing sanitation systems burdened with over a century of capital infrastructure investment and assets that require 30-50 years to pay back, make centralised sanitation both economically unsustainable and institutionally rigid. Social practices associated with water borne sanitation have been embedded within western society for over a century making `radical� system change and the introduction of alternative technologies and habits of practice challenging.

2009-01-01T00:00:00Z Du Haiping Zhang Nong http://hdl.handle.net/10453/12811 2013-02-28T03:33:28Z 2008-01-01T00:00:00Z

Multiobjective Static Output Feedback Control Design for Vehicle Suspensions Du Haiping; Zhang Nong Shigehiko Kaneko et al This paper presents an approach to design multiobjective static output feedback H2 / H.. /GH2 controller for vehicle suspensions by using linear matrix inequalities (LMIs) and genetic algorithms (GAs). A quarter car model with active suspension system is studied in this paper and three main performance requirements for an advanced vehicle suspension are considered. Among these requirements, the ride comfort performance is optimized by minimizing the H2 norm from the road disturbance to the sprung mass acceleration, the road holding performance isimproved by constraining the H.. norm from the road disturbance to the tyre deflection to be less than a given value, and the suspension deflection is guaranteed to be less than its hard limit by constraining the generalized H2 norm from the road disturbance to the suspension deflection. In addition, the controller gain can be constrained naturally in GAs, which can avoid the actuator saturation problem. A static output feedback controller, which only uses the available sprung velocity and suspension deflection signals as feedback signals, is obtained. This multiobjective controller is realized by using GAs to search for the possible control gain matrix and then to resolve the LMIs together with the minimization optimization problem. and the approach is validated by numerical simulation which shows that the designed static output feedback controller can achieve good active suspension performances in spite of its simplicity.

2008-01-01T00:00:00Z